From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from firstgate.proxmox.com (firstgate.proxmox.com [212.224.123.68]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by lists.proxmox.com (Postfix) with ESMTPS id 7001290BE0 for ; Mon, 12 Feb 2024 22:00:15 +0100 (CET) Received: from firstgate.proxmox.com (localhost [127.0.0.1]) by firstgate.proxmox.com (Proxmox) with ESMTP id 562041E11A for ; Mon, 12 Feb 2024 22:00:15 +0100 (CET) Received: from proxmox-new.maurer-it.com (proxmox-new.maurer-it.com [94.136.29.106]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by firstgate.proxmox.com (Proxmox) with ESMTPS for ; Mon, 12 Feb 2024 22:00:13 +0100 (CET) Received: from proxmox-new.maurer-it.com (localhost.localdomain [127.0.0.1]) by proxmox-new.maurer-it.com (Proxmox) with ESMTP id 90D71479F6 for ; Mon, 12 Feb 2024 22:00:13 +0100 (CET) From: Stoiko Ivanov To: pmg-devel@lists.proxmox.com Date: Mon, 12 Feb 2024 21:59:59 +0100 Message-Id: <20240212210000.32989-2-s.ivanov@proxmox.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240212210000.32989-1-s.ivanov@proxmox.com> References: <20240212210000.32989-1-s.ivanov@proxmox.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SPAM-LEVEL: Spam detection results: 0 AWL 0.087 Adjusted score from AWL reputation of From: address BAYES_00 -1.9 Bayes spam probability is 0 to 1% DMARC_MISSING 0.1 Missing DMARC policy KAM_DMARC_STATUS 0.01 Test Rule for DKIM or SPF Failure with Strict Alignment SPF_HELO_NONE 0.001 SPF: HELO does not publish an SPF Record SPF_PASS -0.001 SPF: sender matches SPF record T_SCC_BODY_TEXT_LINE -0.01 - Subject: [pmg-devel] [PATCH pmg-api 1/2] templates: postfix: adapt to current default setting for smtpsmuggling X-BeenThere: pmg-devel@lists.proxmox.com X-Mailman-Version: 2.1.29 Precedence: list List-Id: Proxmox Mail Gateway development discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 12 Feb 2024 21:00:15 -0000 postfix recently released new versions (for all supported stable versions including 3.7.10), which changed the behavior regarding bare newlines (which originally caused smtp-smuggling [0]). Instead of directly rejecting smtp sessions when is used as command separator, the session continues, however a bare is not recognized as end for the DATA command. The current setting of `smtpd_forbid_bare_newline = yes` (in 3.7.9) used to behave like the new setting of 'reject'. In 3.7.10 this was changed and it behaves like `smtpd_forbid_bare_newline = normalize` (the default for postfix > 3.9) The current patch simply adapts to the current default naming (yes is an alias for normalize) - The change in behavior came with the postfix update shipped in proposed-updates end of January and part of Debian 12.5 (released on 10.02.2024). As both versions mitigate smtp-smuggling in postfix, and even the more drastic behavior of rejecting bare did not cause any problems in our support-channels and own deployments the patch is not security-relevant. [0] https://www.postfix.org/smtp-smuggling.html [1] https://metadata.ftp-master.debian.org/changelogs//main/p/postfix/postfix_3.7.10-0+deb12u1_changelog Signed-off-by: Stoiko Ivanov --- src/templates/main.cf.in | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/templates/main.cf.in b/src/templates/main.cf.in index 3b56355..e686884 100644 --- a/src/templates/main.cf.in +++ b/src/templates/main.cf.in @@ -101,7 +101,7 @@ unverified_recipient_reject_code = [% pmg.mail.verifyreceivers %] smtpd_data_restrictions = reject_unauth_pipelining -smtpd_forbid_bare_newline = yes +smtpd_forbid_bare_newline = normalize smtpd_forbid_bare_newline_exclusions = $mynetworks, cidr:/etc/postfix/clientaccess -- 2.39.2